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International Journal of Ophthalmology(English edition) 2020年第6期13卷 907-912页

作者： mahmoud abdel-radi Zeiad Eldaly Hazem abdelmotaal Reham abdelrahman Mohamed Sayed Kamel Soliman Department of Ophthalmology Assiut UniversityAssiut 71516Egypt

AIM:To compare corneal demarcation line(DL)depth in both accelerated epithelium-off and trans-epithelium cross linking(CXL)using anterior segment optical coherence tomography(AS-OCT)and its relation to maximum keratometry(Kmax)progression in both ***:A prospective comparative interventional study where patients with mild to moderate keratoconus(KC)were classified into two groups:accelerated epitheliumoff and trans-epithelium CXL based on corneal *** of corneal DL depth was carried out after 3mo by *** readings were evaluated after one year follow up using the Scheimpflug imaging ***:Study included 74 eyes of 44 *** A underwent epithelium-off CXL(41 eyes),while Group B underwent trans-epithelium CXL(33 eyes).At 3mo follow up,mean corneal DL depth in Group A was 219.9±58.4μm while in Group B was 127.2±7.8μm(P0.05).In addition,no significant change in corneal pachymetry was found in both groups(meanchange at 1y:6.4±4.7 and-10.1±2.3μm in Groups A and B respectively).CONCLUSION:Despite a significantly deeper corneal DL depth created by accelerated epithelium-off CXL technique compared to accelerated trans-epithelium CXL,there is no significant impact on keratoconus progression.

关键词： anterior segment optical coherence tomography cross linking demarcation line keratoconus

Performance Comparison of Hyper-V and KVM for Cryptographic Tasks in Cloud Computing

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Computers, Materials & Continua 2024年第2期78卷 2023-2045页

作者： Nader abdel Karim Osama A.Khashan Waleed K.Abdulraheem Moutaz Alazab Hasan Kanaker mahmoud E.Farfoura Mohammad Alshinwan Department of Intelligent Systems Faculty of Artificial IntelligenceAl-Balqa Applied UniversityAl-Salt1705Jordan Research and Innovation Centers Rabdan AcademyP.O.Box 114646Abu DhabiUnited Arab Emirates Department of Information Systems and Networks TheWorld Islamic Sciences and Education UniversityAmman11947Jordan Department of Cyber Security Isra UniversityAmman1162Jordan Faculty of Science and Information Technology Al-Zaytoonah University of JordanAmman11733Jordan Middle East University Research Unit Middle East UniversityAmman11831Jordan

As the extensive use of cloud computing raises questions about the security of any personal data stored there,cryptography is being used more frequently as a security tool to protect data confidentiality and privacy in the cloud environment.A hypervisor is a virtualization software used in cloud hosting to divide and allocate resources on various pieces of *** choice of hypervisor can significantly impact the performance of cryptographic operations in the cloud *** important issue that must be carefully examined is that no hypervisor is completely superior in terms of performance;Each hypervisor should be examined to meet specific *** main objective of this study is to provide accurate results to compare the performance of Hyper-V and Kernel-based Virtual Machine(KVM)while implementing different cryptographic algorithms to guide cloud service providers and end users in choosing the most suitable hypervisor for their cryptographic *** study evaluated the efficiency of two hypervisors,Hyper-V and KVM,in implementing six cryptographic algorithms:Rivest,Shamir,Adleman(RSA),Advanced Encryption Standard(AES),Triple Data Encryption Standard(TripleDES),Carlisle Adams and Stafford Tavares(CAST-128),BLOWFISH,and *** study’s findings show that KVM outperforms Hyper-V,with 12.2%less Central Processing Unit(CPU)use and 12.95%less time overall for encryption and decryption operations with various file *** study’s findings emphasize how crucial it is to pick a hypervisor that is appropriate for cryptographic needs in a cloud environment,which could assist both cloud service providers and end *** research may focus more on how various hypervisors perform while handling cryptographic workloads.

关键词： Cloud computing performance virtualization hypervisors Hyper-V KVM cryptographic algorithm

Calculation of ship motions in steep waves with restoring and Froude-Krylov forces on an adaptive panel mesh with Gauss and analytic integration methods

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Journal of Hydrodynamics 2024年第2期36卷 275-289页

作者： Malwin Wermbter Moustafa abdel-Maksoud Institute for Fluid Dynamics and Ship Theory Hamburg University of TechnologyHamburgGermany

The impulse response method is a frequently used method to calculate ship seakeeping *** this paper,the restoring and Froude-Krylov calculation is conducted with constant evaluation of panel pressures as well as Gauss quadrature and an analytical *** applied panel grid is coarsened by an adaptive algorithm which is based on a normal vector *** comparison of methods is based on grid convergence studies which are followed by a verification of forces with computational fluid dynamics(CFD)results on the fixed duisburg test case in *** with experimental results in head,oblique and following waves show that all integration methods are *** exact integration is numerically sensitive in some *** quadrature is highly accurate;however,the additional effort is not beneficial since the geometrical accuracy has-stronger influence on the force amplitudes than the integration *** grid coarsening reduces the simulation time and is accurate up to a level,where the panel length comes close the *** added resistance at the investigated Froude number of 0.05 shows higher uncertainty levels,this applies to the results of both the numerical methods and model tests.

关键词： Ship hydrodynamics seakeeping impulse response method added resistance wave loads

Bearing capacity of circular footings on multi-layered sand-waste tire shreds reinforced with geogrids

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1085-1094页

作者： mahmoud Ghazavi Ehsan Khosroshahi Faculty of Civil Engineering K.N.Toosi University of TechnologyTehranIran

The presence of waste tires poses an environmental challenge as they occupy a significant amount of land and are expensive to dispose in ***,reusing waste tires can address this issue when waste tires are used in geotechnical *** determine the viability of this approach,laboratoryscale tests were conducted to investigate load-bearing capacity of circular footings on sand-tire shred(STS)mixtures with shredded waste tire contents of 5%e15%by weight and three different widths of *** investigation focused on analyzing the thickness of layers composed of STS mixtures,the soil cap,and the impact of geogrids on bearing *** results indicate that a specific mixture of sand and tire shreds provides the highest footing-bearing *** addition,the optimal shred content and size were found to be 10%by weight and 2 cm×10 cm,***,for a given tire shred width,a particular length provides the largest bearing *** results agree well with that of previous research conducted by the first author and his colleagues in direct shear and California bearing ratio(CBR)*** primary finding of this research is that the use of two-layered STS mixtures reinforced by geogrids significantly enhances the bearing capacity.

关键词： Geogrid Sand Waste tire shred Bearing capacity Waste tire shred optimization Tire shred aspect ratio

Source localization based on field signatures:Laboratory ultrasonic validation

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Journal of Electronic Science and Technology 2024年第3期22卷 47-56页

作者： mahmoud Eissa Dmitry Sukhanov Department of radiophysics Tomsk State UniversityTomsk634050Russia Higher Institute for Applied Sciences and Technology(HIAST) Damascus31983Syria

Location awareness in wireless networks is essential for emergency services,navigation,gaming,and many other *** article presents a method for source localization based on measuring the amplitude-phase distribution of the field at the base *** existing scatterers in the target area create unique scattered field interference at each source *** unique field interference at each source location results in a unique field signature at the base station which is used for source *** the proposed method,the target area is divided into a grid with a step of less than half the *** grid node is characterized by its field signature at the base *** signatures corresponding to all nodes are normalized and stored in the base station as fingerprints for source *** normalization of the field signatures avoids the need for time synchronization between the base station and the *** a source transmits signals,the generated field signature at the base station is normalized and then correlated with the stored *** maximum correlation value is given by the node to which the source is the *** simulations and results of experiments on ultrasonic waves in the air show that the ultrasonic source is correctly localized using broadband field signatures with one base station and without time *** proposed method is potentially applicable for indoor localization and navigation of mobile robots.

关键词： Base station Field signature Fingerprints Localization Ultrasonic frequencies

A comparative study of bifacial versus monofacial PV systems at the UK’s largest solar plant

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Clean Energy 2024年第4期8卷 248-260页

作者： Ghadeer Badran mahmoud Dhimish School of Physics Engineering and TechnologyUniversity of YorkYorkYO105DDUnited Kingdom

This paper presents an extensive analysis of the UK’s largest bifacial photovoltaic(PV)power plant,located in North *** in January 2020,this trailblazing facility,with a total installed capacity of 34.7 MW,is a benchmark for the evaluation of bifacial solar technology within the *** pioneering study provides a thorough comparative assessment of bifacial and monofacial PV systems through a methodical investigation of their energy production,degradation rates,and spectral responses over a 4-year operational *** findings reveal that bifacial PV modules,distributed across four segments of the power plant,demonstrate a remarkable average power gain ranging between 15.12%and 17.31%compared with monofacial *** experiencing marginally higher annual degradation rates-1.17%for bifacial compared with 0.91%for monofacial systems-bifacial modules show superior resilience and energy yield,particularly during winter months when albedo effects are pronounced due to snow *** study also highlights the strategic importance of spectral response analysis in optimizing PV *** modules have shown greater efficiency in capturing infrared radiation-a property that could be exploited to enhance overall energy yield under specific environmental *** empirical data indicate a consistent performance of bifacial modules with an average normalized energy output clustering around the expected efficiency ***,the results of this study are pivotal for understanding the practical implications of deploying bifacial PV technology on a large *** provide valuable data for stakeholders in the solar energy sector,guiding future installations and innovations in solar panel technology.

关键词： photovoltaic bifacial PV system energy efficiency renewable energy

An extensive analytical and numerical study of the generalized q-deformed Sinh-Gordon equation

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Journal of Ocean Engineering and Science 2024年第3期9卷 232-239页

作者： Khalid K.Ali abdel-Haleem abdel-Aty Mathematics Department Faculty of ScienceAl-Azhar UniversityNasr-CityCairoEgypt Department of Physics College of SciencesUniversity of BishaPO Box 344Bisha 61922Saudi Arabia Physics Department Faculty of ScienceAl-Azhar UniversityAssiut 71524Egypt

In this paper,the q-deformed Sinh-Gordon equation is solved analytically using a new general form based on the extended tanh *** numerical solutions of the equation is obtained using a b-spline finite element ***,we present numerous figures to demonstrate the various solitons propagation *** type of equation has not been previously dealt with in such ways,whether analytical or *** study is very useful in studying several physical systems that have lost their symmetry.

关键词： q-Deformed equation Solitos solutions The extended tanh method Finite element method q-Calculus

Ultralong hydroxyapatite-based forward osmosis membrane for freshwater generation

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Frontiers of Chemical Science and Engineering 2024年第9期18卷 37-49页

作者： Mohamed Gamal Gomaa Hamdy Maamoun abdel-Ghafar Francesco Galiano Francesca Russo Alberto Figoli El-Sayed Ali abdel-Aal abdel-Hakim Taha Kandil Bahaa Ahmed Salah Central Metallurgical Research and Development Institute(CMRDI) 11421 CairoEgypt Chemistry Department Faculty of ScienceHelwan University11795 CairoEgypt Institute on Membrane Technology(CNR-ITM) 87036 RendeItaly

Increasing global water shortages are accelerating the pace of membrane manufacturing,which generates many environmentally harmful *** challenges need a radical rethink of developing innovative membranes that can address freshwater production without generating environmentally harmful *** work utilized the synthesized ultra-long hydroxyapatite(UHA)by the solvothermal method using the green solvent oleic acid in preparing UHA-based forward osmosis *** membranes were developed using different loading ratios of graphene oxide(GO)by vacuum-assisted filtration *** prepared GO/UHA membranes were identified using X-ray diffraction,scanning electron microscope,Fourier-transform infrared spectroscopy,and X-ray photoelectron *** contact angle and pore size distribution were determined for the obtained GO/UHA *** obtained hierarchical porous structure in the prepared membranes with interconnected channels results in a stable water flux with reverse salt *** best water flux rate of 42±2 L·m^(–2)·h^(–1)was achieved using the 50 mg GO/UHA membrane,which is 3.3 times higher than the pristine membrane,and a reverse salt flux of 67 g·m^(-2)·h^(–1).The obtained results showed a promising capability of a new generation of sustainable inorganic-based membranes that can be utilized in freshwater generation by energy-efficient techniques such as forward osmosis.

关键词： forward osmosis ultra-long hydroxyapatite graphene oxide inorganic-based membrane

Geochemistry of island arc assemblage in the Eastern Desert of Egypt and the role of Pan-African magmatism in crustal growth of the Arabian–Nubian Shield:A review

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Acta Geochimica 2024年第3期43卷 588-622页

作者： abdel-Aal Mabdel-Karim Mohamed MHamdy Adel A.Surour Geology Department Faculty of ScienceZagazig UniversityZagazig 44519Egypt Geology Department Faculty of ScienceTanta UniversityTanta 31527Egypt Department of Geological Sciences Faculty of ScienceNew Galala City 43511Egypt Geology Department Faculty of ScienceCairo UniversityGiza 12613Egypt

Neoproterozoic island arc assemblage of the Arabian–Nubian Shield(ANS)in the Eastern Desert(ED)of Egypt comprises juvenile suites of metavolcanics(MV),large amounts of meta-sedimentary rocks(MS),and voluminous metagabbros-diorites(MGD)and syn-tectonic intrusions of older granitoids(OG).We report here the updates of these four rock units in terms of classification,distribution,chemical characteristics,geodynamic evolution,metamorphism,and *** addition,we discuss these integrated data to elucidate a reasonable and reliable model for crustal evolution in the *** main features of these rock units indicate their relation to each other and the geodynamic environment dominated by early immature oceanic island arcs to primitive continental *** information of the island arc metavolcanic and plutonic rocks(gabbros,diorites,tonalites,and granodiorites)furnish evidence of the genetic *** include proximity and a coeval nature in the field;all protolith magmas are subalkaline in nature following calc-alkaline series with minor tholeiitic affinities;common geochemical signature of the arc rocks and subduction-related magmatism;their similar enrichment in LREEs;and similar major element compositions with mafic melts derived from metasomatized mantle *** volcano-sedimentary and the OG rocks underwent multiphase deformation events whereas the MGD complexes deformed *** on the magmatic,sedimentological,and metamorphic evolutions constrained by geochronological data as well as the progressive evolutionary trend from extensional to compressional regimes,a possible gradual decrease in the subducted slab dip angle is the most infl uential in any geodynamic model for arc assemblage in the ED of Egypt.

关键词： Island arc assemblage Magmatism Crustal growth Neoproterozoic Arabian–Nubian Shield Eastern Desert Egypt

Entrepreneurship training:its influences on innovation potentials among nursing students

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Frontiers of Nursing 2024年第1期11卷 85-98页

作者： Asmaa abdel Rahman abdel Rahman Dalia Abdallah abdelatief Medical Surgical Nursing Department Faculty of NursingAin Shams UniversityCairoEgypt

Objective:To evaluate the influences of entrepreneurship training on the innovation potential among nursing ***:A quasi-experimental design was utilized to conduct this *** study was conducted in the classroom at the faculty of nursing,and the“i Hub”center at Ain Shams University(ASU)in Cairo,Egypt.A purposive sample of 42 nursing students who participated in the“Ain Shams University-innovate”competition from the Faculty of Nursing of ASU were included in this *** collection tools included(1)Nursing students'innovation skills assessment questionnaire and(2)Innovative projects evaluation ***:There was a statistically significant difference between the mean scores of nursing students'total innovation skills pre-and post-implementation of entrepreneurship training,where P-value<***:The results of the current study support the research hypothesis because the implementation of entrepreneurship training positively affects nursing students'innovation *** entrepreneurship education in nursing and integrating it into nursing programs will stimulate creativity,innovation,and entrepreneurship among nursing students and health care services.

关键词： entrepreneurship training innovation potentials nursing students creative skills energy/motivation